Impregnated product and process of manufacture



Patented July 4, 1.933

UNITED STATES PATENT HAROLD J. nosE, or PENN TOWNSHIP, ALLEGHENY COUNTY, PENNSYLVANIA, AND WILLIAM H. HILL, or NEW YORK, N. Y., ASSIGNORS 'ro THE xorrnns coMrANY, or DELAWARE, A CORPORATION or DELAWARE IMPREGNATED PRODUCT AND PROCESS OF MANUFACTURE No Drawing.

' This invention relates'to improvements in impregnated products and a process of manu- 'facturing the same and more particularly-to the impregnation of porous materials with l 6 compositions containing coal 'and/or solutions of coal.

Porous materials such aswood, fabrics 3 made of any kind of fibre, paper, kraft paper,

1 I cardboard, felt, prepared porous compositions ill of various kinds, porous brick or stone, concrete, coke, etc., may be impregnated with coal or coal solutions for the purpose of making them water-proof, resistant to decay or i corrosion; for the purpose' of strengthening !1 and toughening them; to produce an improved wear surface; andfor frictional, ad-

hesive or decorative purposes.

- As set forth in our application Serial No.

A 97,467,'filed March 25, 1926, coal may be dissolved in oils, such as coal "tar or .water-gas tar, and certain distillates therefrom. The

coal and oil are brought together and heated charcoal or fusain which may be present in.

limited amount.

Preferably high boiling coal. tar oil or wate'r-gas-tar oil containing resinous material is used as'a solvent for coal. Petroleum -oils, preferably the' products from cracked petroleum oils and especially the higher boil-1 ing distillates thereof are also used.

A coal solution suitable for use in the present invention may be prepared by heating about 20 to 25 parts of coal in about to parts of high oiling-coke-oven-tar oil,

in a closed vessel heated directly to a temperature of about 300 0. Water and unesirable light oils are allowed to escape before the vessel is closed. Large quantities 1929. Serial No. 362,880.

be increased by heating or by the addition of thinning material such as water-gas tar oils or coal tar oils and the like.

Certain thinning materials called introfiers may also be added. Introfiers are substances which promote the penetration of liquids into porous materials or which produce a thinnin amount a ded. Orthochlorphenol and benzyl alcohol, for instance, have this effect and may be addedpreferably to the extent of about five percent by weight.

Water may also be used as a thinning agent, in which case the coal solution may be in the form of an emulsion.

Coal solution gels prepared in accordance with the disclosure in a copending patent applicationto William H. Hill, Serial No. a

393,115, filed Sept. 15, 1929, now Patent No. 1,875,458, may be used instead of coalsolutions as such. One method of preparing such gels or so-called coagulated coal solutions, is

as follows: A fairly concentrated coal solution, comprising 30 parts of coal in 7 0 parts by weight'of dehydrated coke oven tar, is crushed as fine as possible and digested with one-quarter of its weight ofsolvent naphtha for about twenty-four hours. The resulting mass is homogenized in a mixing machine and then run through a colloid mill.

. Impregnation with coal solutions of any desired consistency may be carried out at atmosphere pressure, or reduced or elevated pressures, or an alternation of high and low pressures maybe used. The material to be impregnated may be heated and or evacuated before the treatment with coal solution occurs.

The porous material may be impregnated with a coal'solution or with a dissolving oil before impregnation with a coal solution which would otherwise wet the material with greater difficulty.

eifect out of proportion to the I or voids in the material treated may be partially filled with a coal solution composition or may be entirely filled. Again, merely the surfaces of the material surrounding the voids or as in the case of fibrous materials, the individual fibres may be merely coated. In certain cases, the individual fibres themselves, especially those of cellular structure, may be impregnated.

The fibres used in connection with this invention may be vegetable fibres such as cotton or grass, animal fibres such as hair or wool, or mineral fibres such as asbestos or mineral wool. The fibres may be loosely or densely matted or woven into webs or pads 01' may be in the form of blocks, sheets or laminations.

The material treated, especially when in the form of thin objects, may be saturated with the coal-solution composition by submerging the material in the composition in liquid form. Where restricted penetration is desired, the surfaces of the objects may be coated with the coal solution composition and the coated material run through cold or heated rollers, or the coal solution composition may be applied with the aid of rollers to one or both sides of the article. This treatment is especially adapted to the continuous treatment of lengths of material such as cloth, tape, cord, paper, asbestos products, etc. a

Limited penetration may also be obtained by brushing or spraying a coal solution composition on the article to be treated and per: mittingit to soak in. Coal solution paint compositions may be very satisfactorily used in this way.

For certain purposes, a porous material may be partially or wholly impregnated with a coal solution composition and a layer of a coal solution composition placed over the surface of the impregnated material. The porous material may be used in this case for reinforcement purposes.

After the impregnation of articles with coal solution'compositions, a part or all of the solvents may be removed by a proper heat treatment with orwithout the recovery of the solvents. For instance, it may be found desirable, for ease of application, to impregnate articles with a more dilute coal solution than would be desired in the final product. In such cases, a subsequent removal from the impregnated material of some of the solventcould be resorted to as indicated above, thus leaving a residue of concentrated coal or coal solution in the pores.

Coal may be pnecipitated from solution by the addition of volatile organic liquids such as gasoline,.-naptha, turpentine, etc. After impregnation, the coal maybe precipitated, when desired, in the pores of the material treatel by saturating with these organic liquids.

'lhedrying of the impregnated material or the removal of solvents or thinners may be accomplished by use of vacuum, by heat ing, by treating with steam or other carrying gases, or by any combination ofthese treatments.

The quality of certain products impreg-. mated with coal solution compositions may I be improved by incorporating .in the coal solution, invarious proportions, finely divided mineral fillers, finely divided coal orcoke, or organic materials either soluble, such as resin, or insoluble materials, such as cellu-' lose .particles, or wood-flour. Substances such as rubber or latex materials may also be incorporated in the impregnating mixture. It is advantageous to include aging or ouring substances such as sulphur or sulphur compounds which will tend to toughen or harden the material during the. above mentioned heat treatment or after a lapse of time.

Accelerators such as diphenylquanidine 0rthiocarbanilide may be used if desired. Al ternatively, coal solution or the oil used as solvent may be treated with sulphur before using it as an impregnating medium.

Porous compositions containing coal may be impregnated with a solvent or coal or with a coal solution. When usiii solvent alone, the coal may be made to dissolve therein by further treatment or while in use.

Also when a composition is prepared from ,coal and a solvent therefor andis put to use under favorable'conditions, the coal will go into solution.

Porous materials impregnated with coal solution compositions are adapted to be used in many ways. An improved friction tape or shoemakers thread of tou h and endur-- ing quality may be prepare above.

- Cotton tape, for instance, is immersed in a warm solution of coal and the saturated tape squeezed between warm metal rollers. The tape may then be passed through a drying oven at about C. or left in the open for a sufficient length of time toproduce a proper surface. Cotton thread may be immersed as indicated in a warm solution of coal and the saturatedcreosoting oil. However, the presence of coal reduces the solubility of the creosote in water and thus helps to reduce, the loss of creosote,due to leaching out by water. As a matter of fact, substantially any coal solution as a normal constituent contains material which inhibits decay, whereas asphalt per se has no such preservative action. Incidentally the cracks in the timber treated become filled with the coal solution and the latter forms an effective sealing means.

In using coal solution compositions as a preservative, they may be employed as sealing compositions for preserving articles by enclosing them in a jacket of porous material such as paper, or cloth made air-tight by impregnating the porous material with a coal solution composition. When sealing food products, a coal solution containing wood tar or wood tar products may be preferred.

Another application of the present invention is in the production of brake bands, brake linings, brake blocks, etc., for automobiles, railway vehicles and other purposes. In preparing such articles, asbestos fabric,- formed or matted asbestos fibre, or other porous compositions, may be impregnated as described above. If desired, part or all of the oil contentof the brake bands and the like, may be removed by direct heating,

Partial or complete carbonization of the coal may be resorted to by further application of heat.

Mulch paper used for agricultural purposes may be considerably improved by impregnating it with a coal solution composi- ,tlOIl.

Porous materials impregnated with coal solution compositions may be employed also in the manufacture of shingles or other roofing materials, expansion joints, rail fillers, floor cloth, and so forth.

We claim as our invention:

1. A porous material having carbonized coal in its pores, said coal having been pre viously in dissolved condition.

' HAROLD J. ROSE. In testimony whereof, I have hereunto subscribed my name this seventh day of May,

WILLIAM H. HILL. 

